Interface a Photoresistor

1//Interface a photoresistor and turn ON and OFF LED based on light intensity
2
3/*Copyright
4  (c) 2019, ProteShea LLC
5All rights reserved.
6
7Redistribution and use in
8  source and binary forms, with or without
9modification, are permitted provided
10  that the following conditions are met:
111. Redistributions of source code must
12  retain the above copyright
13notice, this list of conditions and the following
14  disclaimer.
152. Redistributions in binary form must reproduce the above copyright
16notice,
17  this list of conditions and the following disclaimer in the
18documentation and/or
19  other materials provided with the distribution.
203. Neither the name of the copyright
21  holders nor the
22names of its contributors may be used to endorse or promote products
23derived
24  from this software without specific prior written permission.
25
26THIS SOFTWARE
27  IS PROVIDED BY THE COPYRIGHT HOLDERS ''AS IS'' AND ANY
28EXPRESS OR IMPLIED WARRANTIES,
29  INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
30WARRANTIES OF MERCHANTABILITY AND
31  FITNESS FOR A PARTICULAR PURPOSE ARE
32DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
33  HOLDER BE LIABLE FOR ANY
34DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
35  CONSEQUENTIAL DAMAGES
36(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
37  GOODS OR SERVICES;
38LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
39  CAUSED AND
40ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
41  OR TORT
42(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
43  OF THIS
44SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
45*/
46
47//variable
48  declarations
49int A0value = 0;
50
51void setup() {
52  
53  pinMode(9, OUTPUT);
54       //LED output pin
55  digitalWrite(9, LOW);     //turn LED OFF
56}
57
58void
59  loop() {
60  
61  A0value = analogRead(A0);
62  if (A0value > 90){        //high
63  light intensity
64    digitalWrite(9, LOW);   //turn LED OFF
65  }
66  else{
67                     //low light intensity
68    digitalWrite(9, HIGH);  //turn
69  LED ON
70  }
71}

1//Interface a photoresistor and vary LED brightness based on surrounding  light intensity
2
3/*Copyright (c) 2019, ProteShea LLC
4All rights reserved.
5
6Redistribution  and use in source and binary forms, with or without
7modification, are permitted  provided that the following conditions are met:
81. Redistributions of source  code must retain the above copyright
9notice, this list of conditions and the  following disclaimer.
102. Redistributions in binary form must reproduce the above  copyright
11notice, this list of conditions and the following disclaimer in the
12documentation  and/or other materials provided with the distribution.
133. Neither the name of  the copyright holders nor the
14names of its contributors may be used to endorse  or promote products
15derived from this software without specific prior written  permission.
16
17THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ''AS IS''  AND ANY
18EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
19WARRANTIES  OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
20DISCLAIMED. IN NO  EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE FOR ANY
21DIRECT, INDIRECT, INCIDENTAL,  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
22(INCLUDING, BUT NOT LIMITED TO,  PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
23LOSS OF USE, DATA, OR PROFITS; OR  BUSINESS INTERRUPTION) HOWEVER CAUSED AND
24ON ANY THEORY OF LIABILITY, WHETHER  IN CONTRACT, STRICT LIABILITY, OR TORT
25(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING  IN ANY WAY OUT OF THE USE OF THIS
26SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY  OF SUCH DAMAGE.
27*/
28
29//variable declarations
30int A0value = 0;
31
32void  setup() {
33  pinMode(9, OUTPUT);       //LED output pin
34}
35
36void loop()  {
37  
38  A0value = map(analogRead(A0),0,1023,0,255);     //map 10-bit value  to an 8-bit value
39  analogWrite(9, 255 - A0value);                  //we want  the LED to dim as the brightness increases so have to do 255 - A0value
40
41}

1//Interface a photoresistor and turn ON and OFF LED based on light intensity
2
3/*Copyright  (c) 2019, ProteShea LLC
4All rights reserved.
5
6Redistribution and use in  source and binary forms, with or without
7modification, are permitted provided  that the following conditions are met:
81. Redistributions of source code must  retain the above copyright
9notice, this list of conditions and the following  disclaimer.
102. Redistributions in binary form must reproduce the above copyright
11notice,  this list of conditions and the following disclaimer in the
12documentation and/or  other materials provided with the distribution.
133. Neither the name of the copyright  holders nor the
14names of its contributors may be used to endorse or promote products
15derived  from this software without specific prior written permission.
16
17THIS SOFTWARE  IS PROVIDED BY THE COPYRIGHT HOLDERS ''AS IS'' AND ANY
18EXPRESS OR IMPLIED WARRANTIES,  INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
19WARRANTIES OF MERCHANTABILITY AND  FITNESS FOR A PARTICULAR PURPOSE ARE
20DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT  HOLDER BE LIABLE FOR ANY
21DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR  CONSEQUENTIAL DAMAGES
22(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE  GOODS OR SERVICES;
23LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER  CAUSED AND
24ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,  OR TORT
25(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE  OF THIS
26SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27*/
28
29//variable  declarations
30int A0value = 0;
31
32void setup() {
33  
34  pinMode(9, OUTPUT);       //LED output pin
35  digitalWrite(9, LOW);     //turn LED OFF
36}
37
38void  loop() {
39  
40  A0value = analogRead(A0);
41  if (A0value > 90){        //high  light intensity
42    digitalWrite(9, LOW);   //turn LED OFF
43  }
44  else{                     //low light intensity
45    digitalWrite(9, HIGH);  //turn  LED ON
46  }
47}